What Are The Reasons For The Heating Of Power Cables?

2023-05-24 109

When a power cord passes through a certain load current, it must heat up. As the load current increases, the surface temperature of the cable will be higher. If not dealt with in time, the consequences can be imagined. For example: PVC cable, with core temperature of 70 degrees as the upper limit, the surface temperature will be 5-10 degrees lower. Therefore, the cable surface temperature below 60 degrees is basically safe. From a power maintenance point of view, of course, the lower the better. Next, let's take a look at the reasons for the heating of power cables in the process of operation.


1. The conductor resistance of the cable does not meet the requirements, resulting in the heating of the cable during operation.


2. improper cable selection, resulting in the cable conductor section is too small, overload during operation. After a long time of use, the heat and heat dissipation of the cable will be unbalanced, resulting in heat dissipation.


3. The cable is too densely installed, the ventilation and heat dissipation effect is not good, or the cable is too close to other heat sources, which affects the normal heat dissipation of the cable and may also lead to the cable heating operation.


4. The joint manufacturing process is not good and the crimping is not strict, resulting in excessive contact resistance at the joint and cable heating.


5. cable insulation performance is not good, resulting in low insulation resistance, heating during operation.


6. Partial sheathing of armored cable is damaged, and the water will cause slow destruction of insulation performance, leading to gradual decline of insulation resistance, and also cause heating in the process of cable operation.


After the power cable heats up, if the cause is not found and the fault is removed in time, insulation thermal breakdown will occur after the cable continues to be energized. This can cause the cable to short-circuit and trip, which can cause a fire. So we must pay attention.